KDX backfiring then dying?

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Dzone
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KDX backfiring then dying?

Post by Dzone »

I just picked up a 2 stroke 1990 kdx 200. There was no spark so I looked for the problem and all there was the kill switch got locked somehow. There was spark right away. I cleaned the carb, cleaned gas tank, put fresh 32/1 mix ratio in, cleaned filter and it started right up. But I drive it and it seems to be not reaching its fullest potential. When I drove up a hill in first gear, it totally just stalled and died. I thought it was the carb so I put a carb in from my other exact same model kdx that hauls. It didn't start but kept backfiring and when I throttle to full rpm's, it just backfires some more and dies, as if there isnt enough air, but I did take the filter out, tried it without it at all, and still did the same thing. I put the old carb back in and it doesnt even start now, except when I spray some starting fluid, then it finally start but I let it warm up but when I put it in gear, it just dies (the same way). Stator seems to be okay, gives a bunch of spark. Timing is good too. Compression is magnificent. I just dont know what problem it has. It has a new Fmf power core exhaust on it, so maybe its the exhaust? Im just tired of kicking it and trying to make it run good... So does anyone know what problem it has?
thanks
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SS109
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KDX backfiring then dying?

Post by SS109 »

How are you sure the timing is good? Did you check to see if the woodruff key that locates the flywheel has sheared off? Also, how are your reeds? I would also check for an exhaust obstruction.
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david
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KDX backfiring then dying?

Post by david »

Simple stuff first. Change the spark plug.
'81 KDX 175
'90 KDX 200
'07 Vulcan 2000 Classic LT (totaled 4/25/15)
'82 Honda GL500 (sold)
'96 ZXi 1100 JetSki
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